Piezoelectric Sensor Patents (Class 73/514.34)
  • Publication number: 20110048133
    Abstract: Embodiments of the invention couple a non-linear force to a vibration element such as a piezoelectric cantilever to introduce chaotic, i.e., non-resonant vibration in the vibration element and thereby improve the non-resonant response of the vibration element. By doing so, the vibration element is responsive to a wider frequency range of vibrations and thus may be more efficient in scavenging energy in environments where the vibration frequency is not constant, e.g., in environment subject to multi-mode or random vibration sources.
    Type: Application
    Filed: August 30, 2010
    Publication date: March 3, 2011
    Applicant: UNIVERSITY OF LOUISVILLE RESEARCH FOUNDATION, INC.
    Inventors: Ji-Tzuoh Lin, Bruce Alphenaar
  • Patent number: 7882740
    Abstract: Static and dynamic acceleration as well as static and dynamic angular velocity are detected with a simple structure. An acceleration detecting section includes a weight body, a pedestal around the weight body, flexible plate-like bridge portions, and piezoresistive elements embedded in the upper surface of the bridge portions. An angular velocity detecting section includes a weight body, a pedestal around the weight body, flexible plate-like bridge portions, and piezoelectric elements fixed to the upper surface of the bridge portions. The pedestals are fixed to a device chassis. When the weight body is displaced by acceleration, the plate-like bridge portions are deflected, so that the acceleration is detected based on the change in the electrical resistances of the piezoresistive elements.
    Type: Grant
    Filed: January 23, 2008
    Date of Patent: February 8, 2011
    Assignee: Wacoh Corporation
    Inventor: Kazuhiro Okada
  • Patent number: 7849745
    Abstract: Sensing structures are provided which are designed using non-conventional designs. These sensing structures have improved sensitivity and noise floor at low frequencies.
    Type: Grant
    Filed: September 26, 2007
    Date of Patent: December 14, 2010
    Assignee: Intel Corporation
    Inventors: Li-Peng Wang, Friedel Gerfers, Ming-Yuan He
  • Patent number: 7849744
    Abstract: An oscillation driver circuit includes a gain control amplifier which causes a vibrator to produce driving vibrations by controlling an oscillation amplitude in an oscillation loop, and a comparator which generates a synchronous detection reference signal based on a signal in the oscillation loop. The oscillation driver circuit sets a gain in a first oscillation loop including the vibrator and the comparator to be larger than unity using an output from the comparator, and then causes the vibrator to produce the driving vibrations by controlling an oscillation amplitude in a second oscillation loop including the vibrator and the gain control amplifier in at least one of an oscillation startup state and a sleep mode.
    Type: Grant
    Filed: July 31, 2007
    Date of Patent: December 14, 2010
    Assignee: Seiko Epson Corporation
    Inventors: Masahiro Kanai, Eitaro Otsuka, Naoki Yoshida
  • Publication number: 20100302025
    Abstract: A portable security alarm system including a movement detecting and signal transmitting member for mounting on or proximate to the object whose movement is to be detected, a signal receiving and alarm generating member for receiving a signal from the movement detecting and signal transmitting member and producing a security response, a remote control for actuating and deactuating the signal receiving and alarm generating member, an environmental monitoring member for sensing an environmental condition and providing a signal to the signal receiving and alarm generating member, a visual information gathering member for gathering visual information and providing a signal to the signal receiving and alarm generating member, an audio output member for receiving a signal from the signal receiving and alarm generating member and generating an audio output, and components for delivering a security notification to remote recipients. A security network that includes the alarm system is also disclosed.
    Type: Application
    Filed: May 26, 2009
    Publication date: December 2, 2010
    Inventor: Michael H. Script
  • Publication number: 20100281979
    Abstract: Low cost miniature vector sensors are provided. An acoustic vector sensor is provided that comprises at least one accelerometer to measure at least one component of acoustic particle acceleration, wherein the at least one accelerometer has a resonant frequency within a measurement band of the acoustic vector sensor. In addition, a method is disclosed for measuring an acoustic signal. The method comprises the steps of configuring an array of acoustic vector sensors comprised of at least one accelerometer to measure at least one component of acoustic particle acceleration; operating the at least one accelerometer at a resonant frequency within a measurement band of the acoustic vector sensor; and generating a voltage using one or more of the acoustic vector sensors representative of the acoustic signal as the acoustic signal propagates past the array. The voltage optionally indicates a bearing of the acoustic signal.
    Type: Application
    Filed: May 7, 2009
    Publication date: November 11, 2010
    Applicant: Applied Physical Sciences Corp.
    Inventors: James A. McConnell, Bruce M. Abraham, Scott C. Jensen, Edward P. April, Jason P. Rudzinsky
  • Publication number: 20100270889
    Abstract: An arrangement that converts mechanical energy into electrical energy employs a base member and a cantilever member coupled thereto. The cantilever member has two piezoelectric layers with an air space therebetween. A proof mass is coupled to the cantilever member distal from the base member. The first and second piezoelectric layers are formed of lead zirconate titanate (PZT), and the output voltage of the cantilever member is proportional to the height of the air gap. A piezoresistive accelerometer that is useful for measuring mechanical vibration has a suspension beam and a piezoresistive layer be separated from the suspension beam. A method of monitoring an acoustic vibration utilizes a piezoresistive element having an air-spaced cantilever formed of a piezoelectric material in the vicinity of the system to be monitored and obtains an alternating voltage form the air-spaced cantilever of the piezoresistive element.
    Type: Application
    Filed: June 2, 2008
    Publication date: October 28, 2010
    Inventors: Yong Xu, Zhuo Wang, Qinglong Zheng
  • Publication number: 20100263447
    Abstract: A tri-axis accelerometer includes a proof mass, at least four anchor points arranged in at least two opposite pairs, a first pair of anchor points being arranged opposite one another along a first axis, a second pair of anchor points being arranged opposite one another along a second axis, the first axis and the second axis being perpendicular to one another, and at least four spring units to connect the proof mass to the at least four anchor points, the spring units each including a pair of identical springs, each spring including a sensing unit.
    Type: Application
    Filed: June 28, 2010
    Publication date: October 21, 2010
    Inventors: Zhiyu Pan, Christoph Lang, Gary Yama, Matthias Metz, Markus Ulm
  • Patent number: 7808334
    Abstract: An oscillation driver circuit that drives a physical quantity transducer includes a one-input/two-output comparator. The one-input/two-output comparator includes a shared differential section that compares a voltage signal input from a drive current/voltage conversion amplifier circuit with a given voltage, a first output section that receives a signal output from the differential section, variably adjusts a voltage amplitude of the received signal, and outputs the resulting signal, and a second output section that receives the signal output from the differential section, and outputs a synchronous detection reference signal of which the voltage amplitude is fixed.
    Type: Grant
    Filed: July 22, 2008
    Date of Patent: October 5, 2010
    Assignee: Seiko Epson Corporation
    Inventors: Naoki Yoshida, Masahiro Kanai, Eitaro Otsuka
  • Publication number: 20100242604
    Abstract: A MEMS device has a mass supported at least in part by a spring. Among other things, the spring has first and second layers, and first and a second electrodes. The first and second layers are between the first and second electrodes, and the first and second layers, which are oppositely polarized, form a bimorph.
    Type: Application
    Filed: March 27, 2009
    Publication date: September 30, 2010
    Applicant: ANALOG DEVICES, INC.
    Inventors: Firas Sammoura, Kuang Yang
  • Patent number: 7802475
    Abstract: An acceleration sensor having a vibrating body includes: a base fixed to a pedestal; an oscillating arm extended from the base in a beam-like shape, oscillating transversally in a planer direction at a predetermined resonant frequency. Here, the oscillating arm includes: an oscillating block defined by a through hole opened through a thickness direction at a widthwise center of the oscillating arm, the through hole extending in a lengthwise direction thereof; an added mass being a junction of a distal end of the oscillating block defined by the through hole; and an excitation means installed on the oscillating arm. At this time, the oscillating arm is supported by the base and by the added mass, either in a pseudo-dual anchor structure or a single anchor structure. With the above configuration, the acceleration sensor detects a resonant frequency variability of the vibrating body caused by an inertial effect of the added mass under acceleration.
    Type: Grant
    Filed: September 25, 2007
    Date of Patent: September 28, 2010
    Assignee: Seiko Epson Corporation
    Inventors: Ryuta Nishizawa, Masako Tanaka
  • Publication number: 20100236329
    Abstract: A method for generating electrical power from an acceleration of an object is provided. The method including: vibrating a mass-spring unit upon an acceleration of an object; transmitting a force resulting from the acceleration from the mass-spring unit to the one or more piezoelectric elements; converting the vibration of the mass-spring unit to an electrical energy; and calculating at least one of the force and acceleration based on an output of the one or more piezoelectric elements.
    Type: Application
    Filed: March 23, 2009
    Publication date: September 23, 2010
    Applicant: Omnitek Partners LLC
    Inventors: Jahangir S. Rastegar, Thomas Spinelli
  • Publication number: 20100219789
    Abstract: An apparatus using reconfigurable integrated sensor elements with an efficient energy harvesting capability is described. Each sensor element has sensing and energy harvesting mode. In the sensing mode, the sensor element measures an environmental characteristic by generating electrical charge and outputs a time-encoded signal indicative of the measurement. In the energy harvesting mode, the sensor element itself is used to harvest energy from ambient energy source and makes it available to other sensor elements or circuit components. The sensing element is switched from the sensing mode to the energy harvesting mode when the electrical charge reaches a predetermined threshold. An image sensor device using asynchronous readout for harvesting energy from incident light while generating images is also described.
    Type: Application
    Filed: February 23, 2010
    Publication date: September 2, 2010
    Applicant: The Hong Kong University of Science and Technology
    Inventors: Amine Bermak, Chao Shi, Man Kay Law
  • Patent number: 7783446
    Abstract: A measuring system includes a piezoelectric sensor, two or more charge amplifiers that are provided with different amplification settings and one respective output, and a signal splitter which is disposed between the sensor and the amplifiers. A charge signal received by the piezoelectric sensor is subdivided into two or more partial signals on the signal splitter during a measurement, and each of two or more partial signals is fed to one of the charge amplifiers, is processed therein, and is finally fed to the outputs. The signal splitter preferably encompasses two or more capacitors. The inventive measuring system is used above all for measuring forces, pressures, extensions/expansions, moments, or accelerations.
    Type: Grant
    Filed: April 28, 2005
    Date of Patent: August 24, 2010
    Assignee: Kistler Holding, AG
    Inventors: Leo Amstutz, Max P. Waser, Paul Engeler
  • Publication number: 20100208575
    Abstract: A hard disk drive and its circuit board are disclosed using just two piezoelectric devices to estimate both shock events and rotational vibration instead of the three devices required by the prior art. Also disclosed, an integrated circuit coupling to these two piezoelectric devices generates the signals associated with shock events and rotational vibration and a processor that may use these signals to direct the operations of the hard disk drive and may configure the components of the integrated circuit. The integrated circuit may or may not include the processor.
    Type: Application
    Filed: February 19, 2009
    Publication date: August 19, 2010
    Inventor: Brian K. Tanner
  • Publication number: 20100186509
    Abstract: The invention provides a method of measuring an acceleration by means of a vibrating accelerometer including a piezoelectric vibrating cell, the method having the steps: of exciting the vibration cell by means of an excitation signal at a resonant frequency of the vibrating cell; of calculating an acceleration value from a detection signal that results from the excitation signal; of exciting the vibrating cell with a correction excitation signal at a correction frequency that is different from the resonant frequency; of extracting a correction signal from the detection signal, the correction being representative of an electrical characteristic that is to be corrected; and of combining the correction signal with the detection signal so as to reduce the electrical characteristic that is to be corrected.
    Type: Application
    Filed: July 16, 2008
    Publication date: July 29, 2010
    Inventor: Pierre Loisel
  • Patent number: 7716985
    Abstract: A piezoelectric quartz accelerometer includes a sensitive element, a signal processing circuit, a base, an outer case, and a socket, wherein the sensitive element includes two round piezoelectric quartz wafers, and a supporting frame, wherein the two round piezoelectric quartz wafers are symmetrically mounted on both sides of the center axial line of the supporting frame; the sensitive element further includes an axial shock buffer unit and a transverse retaining unit for protecting overload of the two round piezoelectric quartz wafers; the signal processing circuit includes an oscillation circuit for obtaining frequency signal, a frequency differential forming circuit for extracting signal, a phase lock and times frequency circuit for amplifying signal, compensating zero phase, compensating non-linearization and compensating temperature, and an output circuit.
    Type: Grant
    Filed: October 14, 2007
    Date of Patent: May 18, 2010
    Assignee: Beijing Information Technology Institute
    Inventors: Fuxue Zhang, Wei Zhang
  • Patent number: 7713772
    Abstract: A sensor integrated on a semiconductor device (1), in particular a flow sensor, comprises a measuring element (2) on a membrane (5). In order to prevent a buckling of the membrane (5) a tensile coating (9) is applied. The coating covers the membrane, but it preferably leaves all the active electronic components integrated on the semiconductor chip (1) uncovered, such that their electrical properties are not affected.
    Type: Grant
    Filed: October 3, 2006
    Date of Patent: May 11, 2010
    Assignee: Sensirion AG
    Inventors: Ralph Steiner Vanha, Tommasso Francesco Cilento
  • Patent number: 7692506
    Abstract: An oscillation driver device includes a gain control amplifier, an automatic gain control circuit, and a mode setting circuit. When the mode setting circuit has switched a mode from a normal operation mode to a low power consumption mode, the automatic gain control circuit is disabled, and the gain in an oscillation loop that drives the vibrator changes from a state in which the gain in the oscillation loop is controlled to be unity by the automatic gain control circuit to a state in which the gain in the oscillation loop is set to be larger than unity. When the mode setting circuit has switched the mode from the low power consumption mode to the normal operation mode, the automatic gain control circuit resumes operation, and the gain in the oscillation loop changes from the state in which the gain in the oscillation loop is set to be larger than unity to the state in which the gain in the oscillation loop is controlled to be unity by the automatic gain control circuit.
    Type: Grant
    Filed: July 28, 2008
    Date of Patent: April 6, 2010
    Assignee: Seiko Epson Corporation
    Inventors: Masahiro Kanai, Eitaro Otsuka, Naoki Yoshida
  • Publication number: 20100064804
    Abstract: In a angular rate sensor, a weight and a base are connected directly through piezoelectric bimorph detectors and piezoelectric bimorph exciters each having a bent portion. When acceleration is applied to the weight, the weight is displaced so as to deform the piezoelectric bimorph detectors. Due to this deformation, charges generated in the piezoelectric bimorph detectors are detected so as to detect acceleration. If an angular rate is applied to the weight when the weight is vibrated by the piezoelectric bimorph exciters, Coriolis force is generated in the weight so as to deform the piezoelectric bimorph detectors. Due to this deformation, charges generated in the piezoelectric bimorph detectors are detected so as to detect the angular rate.
    Type: Application
    Filed: March 26, 2009
    Publication date: March 18, 2010
    Inventors: Takashi Kawakubo, Toshihiko Nagano, Michihiko Nishigaki
  • Publication number: 20100064809
    Abstract: Systems and methods are provided for determining mechanical resonance of a sensor. In one embodiment, a system is provided that comprises a bias voltage source configured to apply a bias voltage impulse signal to a terminal of the sensor and a zero crossing detector configured to detect zero crossing cycles of a sensor output signal response to the bias voltage impulse signal. The system further comprises a controller configured to determine the resonance frequency of the sensor based on the detected zero crossing cycles of the sensor output signal response.
    Type: Application
    Filed: September 13, 2008
    Publication date: March 18, 2010
    Inventors: Kenji Toga, Masaki Yamashita
  • Publication number: 20100058861
    Abstract: Transducers comprising a frame structure made of piezoelectric material convert energy, through piezoelectric effect, between electrostatic energy associated with voltage differential between the electrodes sandwiching the frame structure and mechanical energy associated with deformation of the frame structure. Inertial sensors such as gyroscopes and accelerators, including inertial sensors comprising ring resonators, utilize said transducers both to generate oscillations of their resonators and to sense the changes in such oscillations produced, in the sensors' frame of reference, by Coriolis forces appearing due to the movement of the sensors.
    Type: Application
    Filed: September 11, 2008
    Publication date: March 11, 2010
    Applicant: ANALOG DEVICES, INC.
    Inventors: Jinbo Kuang, William Albert Clark, John Albert Geen
  • Publication number: 20100037693
    Abstract: An acceleration sensor has a pair of main surface protection members arranged at one end of both main surfaces of a piezoelectric oscillation element, and spaced from the main surfaces through a pair of main surface spacer members. An end surface protection member is arranged on an end surface at the other end of the main surface protection members by having an interval between the end surface protection member and the piezoelectric oscillation element, through a pair of end surface spacer members. A pair of side surface protection members is arranged at one end of the both side surfaces of the piezoelectric vibration element, the pair of main surface protection members, the end surface protection member, the pair of main surface spacer members, and a pair of side surface spacer members arranged on both side surfaces of the end surface spacer members.
    Type: Application
    Filed: January 29, 2008
    Publication date: February 18, 2010
    Applicant: KYOCERA CORPORATION
    Inventor: Kaoru Matsuo
  • Publication number: 20100005886
    Abstract: The invention provides a sensor comprising a frame, a plurality of beams extending inwardly from said frame, a weight portion supported by the beams, a piezoelectric-resistor formed on each beam and an insulating layer that covers the piezoelectric-resistor. The piezoelectric-resistor has at least one bend, and a metal wiring is located on the insulting layer positioned at the bend. The metal wiring is connected to the bend via at least two contact holes formed in the insulating layer. Contact holes are formed in the insulating layer positioned at both ends of the piezoelectric-resistor, and a bridge circuit wiring is connected to the piezoelectric-resistor via the contact holes.
    Type: Application
    Filed: June 30, 2009
    Publication date: January 14, 2010
    Applicant: DAI NIPPON PRINTING CO., LTD.
    Inventors: Kazuhiko Aida, Katsumi Hashimoto, Toshiaki Mori
  • Patent number: 7628070
    Abstract: The inertial sensor comprises a piezoelectric plate having a vibrator member defined therein that carries excitation electrodes connected to an excitation circuit comprising conductor tracks carried by the piezoelectric plate, the excitation circuit including a disturbing circuit portion in which two conductor tracks extend on either side of a midplane and present a width less than 50 ?m, and preferably equal to 10 ?m, and are spaced apart by a distance of less than 100 ?m, and preferably equal to 40 ?m.
    Type: Grant
    Filed: June 30, 2006
    Date of Patent: December 8, 2009
    Assignee: Sagem Defense Securite
    Inventors: Raphaël Brisson, Paul Featonby
  • Patent number: 7626888
    Abstract: An ultrasound sensor for a vehicle has a housing which is fixedly arranged at a vehicle inner side of a periphery member of the vehicle, an ultrasound vibrator for sending and receiving ultrasound, and an ultrasound transferring member which is constructed of a different material from that of the housing to have an acoustic impedance with a medium value between an acoustic impedance of the ultrasound vibrator and that of the periphery member. The ultrasound vibrator is accommodated in the housing and fixed to an end portion of the housing, which faces the periphery member. The ultrasound transferring member is arranged at the end portion of the housing, and contacts both the ultrasound vibrator and the periphery member of the vehicle.
    Type: Grant
    Filed: November 21, 2006
    Date of Patent: December 1, 2009
    Assignees: Denso Corporation, Nippon Soken, Inc.
    Inventors: Akio Nakano, Takeo Tsuzuki, Yoshihisa Sato, Kiyonari Kojima
  • Patent number: 7624639
    Abstract: An acceleration sensor includes a detection element having a plurality of piezoelectric ceramic layers laminated together and a pair of retaining members that retain an end portion of the detection element in a longitudinal direction thereof at two principal surfaces of the end portion. The detection element includes electrodes between the ceramic layers and on principal surfaces. The detection element obtains a voltage or a charge generated in the detection element in response to an application of acceleration from the principal-surface electrodes and the interlayer electrodes. The piezoelectric ceramic layers are not polarized in areas between the principal-surface electrodes and the interlayer electrodes within a retaining area in which the detection element is retained by the retaining members.
    Type: Grant
    Filed: November 7, 2008
    Date of Patent: December 1, 2009
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Takeshi Eimori, Jun Tabota
  • Patent number: 7608900
    Abstract: An accelerator sensor includes a semiconductor substrate having a main front surface and a main rear surface, a first groove portion being formed along a front surface pattern, in the main front surface, a second groove portion being formed along a rear surface pattern, in the main rear surface, a through-hole being formed because of connection between at least parts of the first groove portion and the second groove portion and at least one groove width variation portion being formed in at least one of inner walls of the first groove portion. An offset of the rear surface pattern to the front surface pattern can be inspected easily by existence of the groove width variation portion.
    Type: Grant
    Filed: August 15, 2006
    Date of Patent: October 27, 2009
    Assignee: Oki Semiconductor Co., Ltd.
    Inventor: Yoshihide Tasaki
  • Patent number: 7565840
    Abstract: An objective is to provide an acceleration sensor element that has a high detection sensitivity and that realizes an accurate measurement of acceleration; and an acceleration sensor including this acceleration sensor element to realize a smaller size and a thinner thickness. An acceleration sensor element comprises a quartz, has a thickness in a Z axis direction, and is formed in a quartz substrate developed in an orthogonal XY plane. A thin-walled section of a bottom section of a concave section of the quartz substrate has a double-ended vibrating reed in which a pair of vibration arms extend in a Y axis direction. When acceleration in a Z axis direction is applied while this double-ended vibrating reed having bending vibration, the acceleration is detected based on a change in a resonance frequency caused when the double-ended vibrating reed deflects in the Z axis direction.
    Type: Grant
    Filed: December 11, 2006
    Date of Patent: July 28, 2009
    Assignee: Epson Toyocom Corporation
    Inventor: Jun Watanabe
  • Publication number: 20090151453
    Abstract: Disclosed is an acceleration sensor having a small variation in detection sensitivity, in which one end portion of an oscillation detecting element is fixed so that the free length thereof does not vary. Supporting resins 4a, 4b are formed in one end portion of the oscillation detecting element 3. With the oscillation detecting element being inserted into a through hole 2h of a holding member 2 provided in a case 1, the supporting resins 4a, 4b are in close contact with the inner periphery of the through hole 2h. As a result, the oscillation detecting element 3 is fixed to and held by the holding member 2.
    Type: Application
    Filed: October 4, 2005
    Publication date: June 18, 2009
    Applicant: KYOCERA CORPORATION
    Inventors: Kazuhisa Momose, Masafumi Hisataka
  • Patent number: 7536913
    Abstract: An underwater acoustic sensor is designed for attachment to a rigid or semi-rigid mounting structure. The sensor includes an outer casing and a secondary casing spaced therefrom. A compliance layer is disposed between the inner surface of the outer casing and the outer surface of the secondary casing. An inner sensor support is designed to attach to the mounting structure and is spaced from the inner surface of the secondary casing. A plurality of sensor elements are disposed between and interconnect the inner surface of the secondary casing and the sensor support.
    Type: Grant
    Filed: November 1, 2005
    Date of Patent: May 26, 2009
    Assignee: The Penn State Research Foundation
    Inventors: Nathan K. Naluai, Gerald C. Lauchle
  • Publication number: 20090084182
    Abstract: A micromechanical sensor element (1) is provided, which has a sealed diaphragm (2) affixed in a frame (3), exhibits high sensitivity at high overload resistance and has a small size, and which allows a piezoresistive measured-value acquisition. To this end, at least one carrier element (4), which is connected to the frame (3) via at least one connection link (5), is formed in the region of the diaphragm (2). Furthermore, piezoresistors (6) for detecting a deformation are situated in the region of the connection link (5).
    Type: Application
    Filed: November 21, 2006
    Publication date: April 2, 2009
    Inventors: Joerg Muchow, Hubert Benzel, Simon Armbruster, Christoph Schelling
  • Patent number: 7509859
    Abstract: An acceleration sensor includes a mass and a supporting member linked by a flexible beam. A strain detector having low-resistance areas at both ends is formed near a boundary between the beam and the mass or between the beam and the supporting member A dielectric film formed on the supporting member and the beam has multiple contact holes disposed over each low-resistance area. Wiring formed on the dielectric film is connected to the low-resistance areas through the contact holes. The provision of multiple contact holes for each low-resistance area extends the life of the acceleration sensor by preventing sensor failure due to the separation or other failure of any single contact.
    Type: Grant
    Filed: December 12, 2007
    Date of Patent: March 31, 2009
    Assignee: Oki Semiconductor Co., Ltd.
    Inventor: Takayuki Kai
  • Publication number: 20090078044
    Abstract: Sensing structures are provided which are designed using non-conventional designs. These sensing structures have improved sensitivity and noise floor at low frequencies.
    Type: Application
    Filed: September 26, 2007
    Publication date: March 26, 2009
    Inventors: Li-Peng Wang, Friedel Gerfers, Ming-Yuan He
  • Publication number: 20090056450
    Abstract: An acceleration sensor includes a detection element having a plurality of piezoelectric ceramic layers laminated together and a pair of retaining members that retain an end portion of the detection element in a longitudinal direction thereof at two principal surfaces of the end portion. The detection element includes electrodes between the ceramic layers and on principal surfaces. The detection element obtains a voltage or a charge generated in the detection element in response to an application of acceleration from the principal-surface electrodes and the interlayer electrodes. The piezoelectric ceramic layers are not polarized in areas between the principal-surface electrodes and the interlayer electrodes within a retaining area in which the detection element is retained by the retaining members.
    Type: Application
    Filed: November 7, 2008
    Publication date: March 5, 2009
    Applicant: MURATA MANUFACTURING CO., LTD.
    Inventors: Takeshi EIMORI, Jun TABOTA
  • Patent number: 7482732
    Abstract: A surface acoustic wave sensor which incorporates: a) a first layered SAW device consisting of a piezoelectric crystal such as lithium niobate or lithium tantalate with interdigital electrodes on its surface, and second piezoelectric layer such as zinc oxide over said interdigital electrodes b) a second layered SAW device consisting of a piezoelectric crystal with interdigital electrodes on its surface, a second piezoelectric layer over said interdigital electrodes and an analyte sensitive surface such as gold on said second piezoelectric layer c) both saw devices are fabricated on the same substrate d) reflectors are located adjacent the interdigital electrodes in each saw device to reduce the bandwidth of the device e) the resonator circuits of each saw sensor incorporate amplifiers which are dependent.
    Type: Grant
    Filed: February 25, 2005
    Date of Patent: January 27, 2009
    Assignee: MNT Innovations Pty Ltd
    Inventor: Kourosh Kalantar-Zadeh
  • Publication number: 20080312565
    Abstract: The present invention provides a CPR sensor that includes a thin and substantially flat flexible substrate having one or more sensor arrays, a power source, an output interface and a processor or analog circuit, all of which are disposed on the substantially flat flexible substrate. The substrate can be any shape (e.g., rectangular, circular, a polygon, an irregular shape that is decorative) and made from a polymer, metal film or other suitable material. Note that the substrate can be rigid or semi-flexible instead of flexible. A protective layer may cover the sensor array, the power source, and the processor or analog circuit. Alternatively, a protective covering can be used to encapsulate the device. The one or more sensor arrays measure one or more of the following compressions characteristics: compression depth, compression force, compression frequency and compression acceleration.
    Type: Application
    Filed: June 15, 2007
    Publication date: December 18, 2008
    Applicants: BOARD OF REGENTS, THE UNIVERSITY OF TEXAS SYSTEM, LAERDAL MEDICAL AS
    Inventors: Zeynep Celik-Butler, John W. Priest, Carolyn L. Cason, Mary E. Mancini, Kenneth George Morallee, Helge Fossan
  • Patent number: 7437260
    Abstract: A semiconductor chip includes a first functional element having a first electronic functional-element parameter exhibiting a dependence relating to the mechanical stress present in the semiconductor circuit chip, and being configured to provide a first output signal, a second functional element having a second electronic functional-element parameter exhibiting a dependence in relation to the mechanical stress present in the semiconductor circuit chip, and being configured to provide a second output signal in dependence on the second electronic functional-element parameter and the mechanical stress, and a combination means for combining the first and second output signals to obtain a resulting output signal exhibiting a predefined dependence on the mechanical stress present in the semiconductor circuit chip, the first and second functional elements being integrated on the semiconductor circuit chip and arranged, geometrically, such that that the first and second functional-element stress influence functions ar
    Type: Grant
    Filed: January 17, 2005
    Date of Patent: October 14, 2008
    Assignee: Infineon Technologies AG
    Inventors: Udo Ausserlechner, Mario Motz
  • Publication number: 20080245149
    Abstract: An acceleration sensor for measuring an acceleration comprises a housing including a measuring-plate, which has a first surface. The measuring plate has a second surface in parallel with and opposite to the first surface. A post is bonded via a post-bonding-face to the first surface. A temperature-compensating-element for compensating a temperature-effect caused by a temperature acting on the measuring-plate, is bonded via an element-bonding-face to the second surface of the measuring-plate. In addition, a sensor as described above is in a measuring device.
    Type: Application
    Filed: October 11, 2006
    Publication date: October 9, 2008
    Applicant: Kistler Holding AG
    Inventors: Andrew Paul Cook, Norton G. Kinsley
  • Publication number: 20080236283
    Abstract: An acceleration sensor includes: a piezoelectric vibration device; an oscillation circuit; and a detection circuit, wherein the piezoelectric vibration device includes a substrate, an insulation layer formed above the substrate, a vibration section forming layer formed above the insulation layer, a vibration section formed in a cantilever shape in a first opening section that penetrates the vibration section forming layer, a second opening section that penetrates the insulation layer and formed below the first opening section and the vibration section, and a piezoelectric element section formed on the vibration section, the oscillation circuit vibrates the piezoelectric vibration device at a resonance frequency, and the detection circuit detects a change in the frequency of vibration of the piezoelectric vibration device which is caused by an acceleration applied in a direction in which the vibration section extends, and outputs a signal corresponding to the acceleration based on the change in the frequency.
    Type: Application
    Filed: March 27, 2008
    Publication date: October 2, 2008
    Applicant: SEIKO EPSON CORPORATION
    Inventors: Takamitsu HIGUCHI, Yasuhiro ONO
  • Publication number: 20080229826
    Abstract: An acceleration sensor includes: a piezoelectric vibration device; an oscillation circuit; and a detection circuit, wherein the piezoelectric vibration device includes a substrate, an insulation layer formed above the substrate, a vibration section forming layer formed above the insulation layer, a vibration section formed in a cantilever shape in a first opening section that penetrates the vibration section forming layer and having a base section affixed to the vibration section forming layer and two beam sections extending from the base section, a second opening section that penetrates the insulation layer and formed below the first opening section and the vibration section, and a piezoelectric element section formed on each of the beam sections; the oscillation circuit vibrates the piezoelectric vibration device at a resonance frequency; and the detection circuit detects a change in the frequency of vibrations of the piezoelectric vibration device which is caused by an acceleration applied in a direction i
    Type: Application
    Filed: March 21, 2008
    Publication date: September 25, 2008
    Applicant: SEIKO EPSON CORPORATION
    Inventors: Takamitsu HIGUCHI, Yasuhiro ONO
  • Publication number: 20080223132
    Abstract: A vibration piezoelectric acceleration sensor including a pair of diaphragms linearly and oppositely disposed on a frame, a support body supporting the diaphragm, and a holding part holding the support body slidably in a linear direction, and another pair of diaphragms disposed linearly and oppositely crossing the pair of diaphragms detecting acceleration in two axes, i.e. X and Y directions. The diaphragms are extended and retracted by the acceleration transmitted to the support body through the holding part, changing a natural oscillation frequency. Accordingly, a high change ratio of resonance frequency can be provided with the detection of the acceleration, and the acceleration in two axes directions can be detected without being affected by a change in temperature.
    Type: Application
    Filed: February 14, 2005
    Publication date: September 18, 2008
    Inventors: Jiro Terada, Masaya Nakatani, Takami Ishida
  • Publication number: 20080216574
    Abstract: The sensor device includes a dead-weight portion, a frame portion disposed so as to surround the dead-weight portion, a supporting portion provided at the frame portion via a first insulating layer, a mass portion provided at the dead-weight portion via a second insulating layer, a beam portion connecting the supporting and mass portions, a first concave portion, and a second concave portion, wherein a depth of the first or second concave portion is from 3.3% or more to 5.0% or less of the width of the frame portion.
    Type: Application
    Filed: March 3, 2008
    Publication date: September 11, 2008
    Applicant: OKI ELECTRIC INDUSTRY CO., LTD.
    Inventor: Akihiko Nomura
  • Publication number: 20080210008
    Abstract: A flexible substrate (110) having flexibility and a fixed substrate (120) disposed so as to oppose it are supported at their peripheral portions by a sensor casing (140). An oscillator (130) is fixed on the lower surface of the flexible substrate. Five lower electrode layers (F1 to F5: F1 and F2 are disposed at front and back of F5) are formed on the upper surface of the flexible substrate. Five upper electrode layers (E1 to E5) are formed on the lower surface of the fixed substrate so as to oppose the lower electrodes. In the case of detecting an angular velocity ?x about the X-axis, an a.c. voltage is applied across a predetermined pair of opposite electrode layers (E5, F5) to allow the oscillator to undergo oscillation Uz in the Z-axis direction. Thus, a Coriolis force Fy proportional to the angular velocity ?x is applied to the oscillator in the Y-axis. By this Coriolis force Fy, the oscillator is caused to undergo displacement in the Y-axis direction.
    Type: Application
    Filed: March 13, 2008
    Publication date: September 4, 2008
    Inventor: Kazuhiro Okada
  • Publication number: 20080202239
    Abstract: Piezoelectric accelerometers and gyroscopes having cantilevered transducers are described.
    Type: Application
    Filed: February 28, 2007
    Publication date: August 28, 2008
    Inventors: R. Shane Fazzio, Kristina L. Lamers, Atul Goel
  • Patent number: 7406948
    Abstract: An engine ECU executes a program including: the step of outputting a fuel-cut instruction when conditions that an accelerator position PA is not higher than a threshold value and a rate of increase DNE of engine speed NE is not lower than a determination value DNE(0) are satisfied; the step of fully closing throttle opening; and the step of suspending ignition of air-fuel mixture by a spark plug.
    Type: Grant
    Filed: July 14, 2006
    Date of Patent: August 5, 2008
    Assignees: Toyota Jidosha Kabushiki Kaisha, Yamaha Hatsudoki Kabushiki Kaisha
    Inventors: Seiji Hirowatari, Masanao Idogawa, Masahiko Teraoka, Fumitoshi Sugiyama, Dai Takida
  • Publication number: 20080179993
    Abstract: A load-bearing structural member has a continuous structural material with piezoelectric material particles mixed in throughout. The structural material may be any of a variety of suitable materials, such as polymer materials, composite materials, ceramic materials, or concrete. The piezoelectric material particles may be used for evaluating the soundness of the structural member, such as in quality control or structural health monitoring processes. The structural member may include one or more conductive pickups used for receiving signals from the structural member. The signals may be induced by introducing ultrasonic signals or vibrational resonance signals into the structural member. The response from such induced signals may be used for quality control purposes or structural health monitoring.
    Type: Application
    Filed: January 30, 2007
    Publication date: July 31, 2008
    Inventor: Terry M. Sanderson
  • Publication number: 20080173092
    Abstract: A motion sensor may include, but is not limited to, a substrate, a beam, a weight, a piezoelectric film, and a first electrode. The beam is supported by the substrate. The beam is elastically deformable. The weight is attached to the beam. The piezoelectric film follows and extends along at least a part of the beam. The piezoelectric film may include, but is not limited to, an organic piezoelectric film. The first electrode is disposed on the piezoelectric film.
    Type: Application
    Filed: January 23, 2008
    Publication date: July 24, 2008
    Applicants: YAMAHA CORPORATION, Tokyo Institute of Technology
    Inventors: Atsuo Hattori, Kentaro Nakamura
  • Publication number: 20080127727
    Abstract: The invention relates to a piezoelectric sensor which comprises a piezoelectric measuring transducer, an amplifier circuit and also at least one connection for external current or signal lines, these elements being integrated on or in a carrier structure. The sensor thereby enables measurement under different temperature conditions. The piezoelectric sensor according to the invention is used for oscillation, acceleration or deflection measurement, in particular in mechanical engineering, in air and space travel or in the automobile industry.
    Type: Application
    Filed: February 14, 2006
    Publication date: June 5, 2008
    Applicant: Fraunhofer-Gesellschaft Zur Forderung Der Angewandten Forschung E.V.
    Inventors: Bernhard Brunner, Dieter Sporn, Gerhard Domann, Peter Spies, Frank Forster, Javier Gutierrez Boronat, Ruth Houbertz-Krauss
  • Publication number: 20080129150
    Abstract: The present invention is directed to sensors that use wide band gap piezoelectric films such as aluminum nitride and zinc oxide. The films can be deposited with chemical and physical methods and etched or micro machined into miniature and micro sensing elements. Various piezoelectric sensing structures such as compression mode and cantilever-type accelerometers, diaphragm-type pressure sensors, and micro sensor arrays can be manufactured with the sensing elements. They can be used in the measurements of vibration, shock, dynamic pressure, stress, and high resolution ultrasound non-destructive test at high temperature up to 800-1000° C.
    Type: Application
    Filed: December 5, 2007
    Publication date: June 5, 2008
    Inventor: Hongxi Zhang